INFO: task kworker/u4:1:11 blocked for more than 143 seconds.
Not tainted 6.1.134-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:1 state:D stack:19736 pid:11 ppid:2 flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:4)
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x143f/0x4570 kernel/sched/core.c:6561
schedule+0xbf/0x180 kernel/sched/core.c:6637
rwsem_down_write_slowpath+0xea1/0x14b0 kernel/locking/rwsem.c:1189
f2fs_down_write fs/f2fs/f2fs.h:2178 [inline]
f2fs_balance_fs+0x4fb/0x6c0 fs/f2fs/segment.c:428
f2fs_write_inode+0x4be/0x660 fs/f2fs/inode.c:733
write_inode fs/fs-writeback.c:1460 [inline]
__writeback_single_inode+0x67d/0x11e0 fs/fs-writeback.c:1677
writeback_sb_inodes+0xc2b/0x1b20 fs/fs-writeback.c:1903
__writeback_inodes_wb+0x114/0x400 fs/fs-writeback.c:1974
wb_writeback+0x4b1/0xe10 fs/fs-writeback.c:2079
wb_check_background_flush fs/fs-writeback.c:2145 [inline]
wb_do_writeback fs/fs-writeback.c:2233 [inline]
wb_workfn+0xc9e/0x1020 fs/fs-writeback.c:2260
process_one_work+0x917/0x1260 kernel/workqueue.c:2292
worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
kthread+0x28d/0x320 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Showing all locks held in the system:
4 locks held by kworker/u4:1/11:
#0: ffff88801ce60138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267
#1: ffffc90000107d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267
#2: ffff8880587c80e0 (&type->s_umount_key#88){++++}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:415
#3: ffff88802437d1e8 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2178 [inline]
#3: ffff88802437d1e8 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_balance_fs+0x4fb/0x6c0 fs/f2fs/segment.c:428
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8d32e910 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8d32f110 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
#0: ffffffff8d32e740 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8d32e740 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8d32e740 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6510
2 locks held by getty/4004:
#0: ffff888030eb1098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc9000325e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x54a/0x1620 drivers/tty/n_tty.c:2198
2 locks held by kworker/u4:8/4377:
#0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267
#1: ffff8880b8e27788 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x419/0x790 kernel/sched/psi.c:999
4 locks held by syz.4.177/5513:
6 locks held by kworker/0:19/7383:
#0: ffff888142e8a538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267
#1: ffffc900038a7d20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267
#2: ffff8880283f7190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:837 [inline]
#2: ffff8880283f7190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1fe/0x5730 drivers/usb/core/hub.c:5813
#3: ffff8880285024f8 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3172 [inline]
#3: ffff8880285024f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5385 [inline]
#3: ffff8880285024f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5629 [inline]
#3: ffff8880285024f8 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5785 [inline]
#3: ffff8880285024f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x2471/0x5730 drivers/usb/core/hub.c:5867
#4: ffff888144f7de68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5386 [inline]
#4: ffff888144f7de68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5629 [inline]
#4: ffff888144f7de68 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5785 [inline]
#4: ffff888144f7de68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x249e/0x5730 drivers/usb/core/hub.c:5867
#5: ffff8880b8e3a998 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537
1 lock held by syz.4.514/7700:
2 locks held by rm/7746:
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.134-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x1ca/0x430 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
watchdog+0xf88/0xfd0 kernel/hung_task.c:377
kthread+0x28d/0x320 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 5435 Comm: kworker/u4:16 Not tainted 6.1.134-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:__should_failslab+0x2/0xf0 mm/failslab.c:18
Code: fd ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 26 fd ff ff 48 89 df e8 9d 7f ff ff e9 19 fd ff ff 00 00 cc cc 00 00 cc cc 41 57 <41> 56 41 54 53 89 f3 49 89 fe 48 c7 c0 c8 2b 41 97 48 c1 e8 03 49
RSP: 0018:ffffc90003827a78 EFLAGS: 00000246
RAX: 0000000004208060 RBX: 00000000000000f0 RCX: dffffc0000000000
RDX: ffffc90003827af0 RSI: 0000000000000a20 RDI: ffff888019a6e280
RBP: 0000000000000a20 R08: 0000000000000a20 R09: fffffbfff225706a
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: ffff888019a6e280 R14: ffffc90003827af0 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fefc137d2d8 CR3: 000000000d08e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
should_failslab+0x5/0x20 mm/slab_common.c:1440
slab_pre_alloc_hook+0x59/0x300 mm/slab.h:712
slab_alloc_node mm/slub.c:3318 [inline]
kmem_cache_alloc_node+0x52/0x310 mm/slub.c:3443
__alloc_skb+0xd3/0x2c0 net/core/skbuff.c:505
alloc_skb include/linux/skbuff.h:1271 [inline]
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline]
nsim_dev_trap_report_work+0x24c/0xab0 drivers/net/netdevsim/dev.c:851
process_one_work+0x917/0x1260 kernel/workqueue.c:2292
worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
kthread+0x28d/0x320 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295